1. Field of the Invention
This invention relates generally to tuner units and, more particularly, to a tuner unit including a frame chassis formed by a metal plate and a unit board held by the frame chassis.
2. Description of the Prior Art
There is an example of a tuner unit of this kind as disclosed in a publication of Japanese Utility Model Laid-open No. S63-77400[H05K 9/00, 1/14, 7/14] laid open on May 23, 1988.
This prior art has a metal pin terminal provided in a lower end of its unit board. The metal pin terminal is inserted in a hole of a main board so that the metal pin terminal can be connected by soldering to a circuit pattern on the main board, thereby assembling a tuner unit onto the main board.
However, the prior art tuner unit requires to prepare a metal pin terminal and then insert the metal pin terminal to the unit board in advance of mounting the tuner unit onto the main board. Thus, the prior art has involved a problem of requiring excessive labor and time and hence cost.
Therefore, it is a primary object of the present invention to provide a novel tuner unit.
Another object of the invention is to provide a tuner unit that is low in price.
A tuner unit according to the present invention is a tuner unit having a frame chassis and a unit board to be mounted on the frame chassis and having on a surface thereof a first circuit pattern to be electrically connected to a second circuit pattern formed on a surface of a main board, comprising: a first protrusion formed at a lower end of the unit board and to be inserted in a first hole of the main board; a terminal pattern formed on the first protrusion and extended from the first circuit pattern; and urging means formed on the frame chassis to urge toward the second circuit pattern a surface having the terminal pattern of the first protrusion inserted in the first hole.
When mounting the tuner unit onto the main board, if the first protrusion of the unit board is inserted in the first hole, the urging means provided on the frame chassis causes the terminal pattern to be urged toward the second pattern of the main board. Thus, the terminal pattern and the second circuit pattern are brought close to each other. Accordingly, by merely soldering the main board with the tuner unit mounted on the main board, the terminal pattern can be connected directly to the second circuit pattern.
Incidentally, where the frame chassis includes a metal plate and a second protrusion formed in a lower end of the metal plate and to be inserted in a second hole of the main board, the urging means is formed on the second protrusion. More specifically, the urging means includes a tapered side face formed on the second protrusion so that the tapered side face and an inner peripheral edge of the second hole can cooperate to urge the first protrusion of the unit board when inserting the second protrusion in the second hole.
The tapered side face has a corresponding distance of a slant to an amount of displacement by which the first protrusion is to be urged.
According to the present invention, the first circuit pattern of the unit board and the second circuit pattern of the main board can be electrically connected by merely inserting and soldering the unit board directly to the main board. Thus, there is no need of separately preparing a metal pin terminal as required in the conventional, resulting in considerable cost reduction.
The above described objects and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.